Cold Water Immersion—It’s a Matter of Life or Death

Forget the 120 Rule, so says Moulton Avery, whose cold water safety presentation I had the pleasure of attending. Avery used the May 16, 2010 tragedy of Irina McEntee and Carissa Ireland in Casco Bay, Maine, as the driving force to start the National Center for Cold Water Safety and to start off the presentation. Nothing like a wake-up call.

What’s the 120 Rule? It’s a rule paddlers use to decide when it’s safe to paddle without wearing some form of immersion wear like a dry suit or wetsuit. Basically, you add the water and air temperatures together, and when the combined total is greater than 120° F, then it’s safe to paddle without immersion wear. The problem is, it’s worthless, says Avery.

Avery stresses that paddlers should dress for the water temperature. In the tragedy of Irina and Carissa, the air temperature was warm the day they set out to paddle, but the water temperature was only 48° F. Authorities believe the girls died within minutes of capsizing. How is that possible?

The body experiences four stages of immersion, according to Avery and outlined on the National Center for Cold Water Safety’s website. The first stage is cold shock, followed by physical incapacitation, hypothermia, and “circumrescue” collapse.

During stage one when you capsize in water with a temperature between 50° - 60° F, your body experiences maximum cold-water shock, resulting in a loss of breathing control. The immediate response is sudden, deep gasps. If you’re underwater when this happens, you end up sucking water into your lungs and drowning. After gasping for air, you begin to hyperventilate. When you hyperventilate, your body blows off carbon dioxide, (CO2), which leads to dizziness, faintness, a ringing in the ears, cramping in muscles, numbness in fingers and toes, and loss of consciousness. You also can’t synchronize your swimming strokes with your breathing, causing you to drown from swimming failure.

You also will find it hard to hold your breath. Under normal circumstances, you might be able to hold your breath for a minute. However, under maximum cold-water shock, that time may decrease to just several seconds.

Cold water on your extremities causes blood vessels in the arms and legs to constrict, which increase the blood pressure in your body’s core. If you suffer from high blood pressure or clogged blood vessels, especially around the heart, you could wind up suffering a heart attack or stroke and death.

Cold water shock also affects your ability to make rational decisions because it affects your mental capacity, leading to disorientation, freezing in place (akin to a deer in the headlights), panic, fear, lethargy, failure to act, and an inability to evaluate options.

The second stage is physical incapacitation—you literally lose the ability to move your arm, legs, hands, feet, fingers, and toes. You find yourself becoming weaker and unable to self-rescue or swim. If you’re not wearing a PFD, at this point you’re very likely to drown because you can’t keep your head above water. Waves have a tendency of wanting to turn your body so that you’re facing the waves. Without the use of your muscles, you’re unable to keep your back turned to the waves, so you end up swallowing water and drowning. You also find it hard holding your head above water.

During stage three, your body begins to suffer from hypothermia. If you’ve reached this stage, you’re in a serious medical emergency. Hypothermia occurs at that point when your body’s core temperature drops below 95° F. The amount of time it takes you to become hypothermic can vary depending on the water temperature, your body fat content, and the clothing you’re wearing. On average, it’s about 30 minutes.

Stage four is referred to as “circumrescue” collapse. Little is known about the condition. It can happen before or during rescue when you’re in or out of the water. It seems to occur as a result of an abrupt loss in blood pressure and can lead to unconsciousness and death.

I’ve tried to address the dangers of capsizing in cold water. There are steps you can take to prevent cold-water shock and the dangers associated with it. The biggest step is wearing the proper clothing and a PFD. It’s not good enough, however, to simply wear a dry suit or wetsuit. You need to make sure that what you wear under the dry suit or the thickness of the wetsuit is adequate to protect you from the cold.

Avery discusses five golden rules to make sure what you’re wearing is adequate for the water you might find yourself in should you capsize.

1. Always wear your PDF.

2. Always dress for the water temperature.

3. Field test your gear.

4. Swim test your gear every time you go out.

5. Imagine the worst that could happen and plan for it.

Most of these rules are self-explanatory. But what does it mean to field test and swim test your gear?

Field testing your gear means to try it out in the water on which you’ll be paddling. Does it keep you warm, and for how long? Do you need gloves and a hood? How thick of gloves do you need? Should you wear gloves under your pogies? The answer, by the way, is yes if you’ll be paddling in cold water. Pogies do nothing to protect your hands once you’re in the water.

When you swim test your gear, you’re checking to make sure that you’ve properly zipped up your dry suit and that relief zipper. It allows you to determine how well you can swim or tread water in the gear. It will also point out weak gaskets and holes in the suit.

IMPORTANT: If you’re shivering, you’re already experiencing a serious situation and need to seek warmth immediately.

I’ve only scratched the surface of cold-water safety. I recommend visiting www.coldwatersafety.org to learn more.